Drill steel centralizer



June' 3, 1941. w, A, sivlrrH, JR

l DRILL STEEL GENTRALIZER .Filed March 7, 1959 WML/,4M A. 5/V/7/1 JE. BY l ATTORNEY Patented June 3, 1941 i geen? einer;

DRILL STEEL CENTRALIZER William A. Smith, Jr., Cleveland, Ohio, assigner to The Cleveland Rock Drill Company, 4Cleve-H land, Ohio, a corporation of Ohio application March 7, 1939, serial No. 260,343

4 claims. y(ci. 255.-45) l This invention relates broadly to rock drills, but more particularly to a centralizer for drilling steels operated by a rock drill of the drifter type.

One object of this invention is to provide a rock drill with an efficient drill steel centralizer for maintaining the drill steel in perfect alignment with the drill when starting a drill hole.

Another object of this invention is to produce a drill steel centralizer constructed and disposed in a manner enabling it to be automatically moved into inoperative position -by the drill during its feeding motion to the work, the centralizer being characterized by a simple construction which is strong, durable .and efficient.

Other objects and advantages more or less ancillary to the foregoing reside in the specific construction and aggroupment of the elements peculiar to this structure, as will become apparent from a more vcomplete examination of this specication.

In the drawing:

Fig. 1 is a side elevational View of the iront end of a rock drill embodying the invention.

Fig. 2 is a top plane view looking in the direction of the arrows 2-2 in Fig, l.

Fig. 3 is a View similar to Fig. l showing the centralizer in inoperative position.

Fig. 4 is a cross sectional View taken in a plane indicated by line l-t in Fig. l.

Fig. 5 is a longitudinal sectional View taken in a plane indicated by line 5-5 in Fig. 4.

Fig. 6 is an end view looking in the direction of the arrows @-5 in Fig. 3.

Referring to the drawing, it represents the front end of a rock drill slidably mounted on a stationary shell ll for feeding to the work a drill steel I2 operatively mounted within the front end i6, and terminated by a cutting end or bit i3 engageable with the work. To the iront end of the shell il, there is rigidly secured by bolts lli a support i5 extending longitudinally therefrom and having its -free end formed with two laterally spaced apertured lugs i6 having a stationary horizontal bolt or pivot l'l extending therethrough transversally of the support and held in position by a.' nut IB. Rotatable on the pivot Il between the lugs l, there is the base of a T-shaped arrn i9 having the ends of its cross head 2Q each formed with an apertured lug 2l located rearwardly of the body of the arm. In each lug 2 l, there is rotatably mounted a vertical shaft or pivot 22 perpendicular to the pivot il and extending transversally of the support. The pivot 22 is secured against endwise movement in one direction by a nut 23 and in the other direction by a finger 2li, which nger eX- tends laterally from the pivot 22 and is terminated by a, drill steel guiding end 25 adapted to fit partway .around the drill -steel l2. In order to enable horizontal swinging movement of the ngers 24 without interference from the drill steel l2, the pivots 22 are located rearwardly of the drill steel guiding ends 25 relative to the cutting end i3 of the drill steel l2. The lugs 2i each carries a stop 2S, the .purpose of which will be explained later. In the arm i5), there is provided a spring pressed plunger 2l engageable with flats 28 and 29 formed on the stationary pivot l'l and disposed at from each other, which plunger and its component spring 3B are held in operative position by a removable plug 3i. Each apertured lug 2l is also provided wit-h a spring pressed plunger -32 located within a. bore 33 closed. iby a plug 3Q, which plunger is engageable with `angularly disposed ats 35 and Sii formed on the pivots 22.

In the operation of the device, when the drill `steelcentralizer is positioned as shown in Fig. 1,

the end 25 of the fingers 2?, are partly surrounding the drill steel l2 as shown in Fig. 4, thereby preventing lateral movement of the drill steel when starting the drill hole. As the rock drill is fed forwardly to the work, the front end l0 will rst engage the ngers E@ of the centralizer to rotate them longitudinally relative to the support into the position shown in the dotted line in Fig. 2, that is, into operative engagement of the stops 26. This swinging motion of the iingers 24 is possible without interference from the drill steel I2 due to the position of their pivots 22 rearwardly of their drill steel vguiding ends 25. In this instance, the ngers yplungers 32, previously engaging the flats 35 to maintain the nngers in operative position, will now engage the flats 36 to maintain the fingers in inoperative position against accidental rotation. After the lingers are engaging the stops 26, the front end l0 acting on the fingers will cause the swinging movement of the arm i9 in a clockwise direction in Fig. 1 or longitudinally relative to the support, to shift the centralizer into inoperative position as shown in Fig. 3. During this swinging movement of the arm i9, the spring pressed plunger 21 will pass over the junction of the flats 2E and 29- formed on the stationary pivot ll and finally engage the flat 29 to maintain the centralizer in inoperative position. The centralizer being now located out of the path of the rock drill, will enable further drilling operation or feeding movement of the rock drill without interference.

When the rock drill has been moved back preparatory .to the drilling of another hole, the arm IS of the centralizer may manually be shifted yfrom the position shown in Fig. 3 tothe position in Fig, 1 and be held in that position by the engagement of the spring pressed plunger 21 with the flat 2t. Subsequently each finger 24 may also be manually shifted into operative position relative to the drill steel I2 and be held in that position against accidental rotation by the spring pressed plungers 32 engaging the flat 3:5.

From the foregoing description, it will be understood .thatrthe cenftralizer when in operative position, as shown in Fig. l is automatically shifted into the inoperative position shown in `Fig. 3 due to the feeding motion of .the rock drill relative to the shell lil, thus enabling the drilling operation to take place with-out interference from the centralizer.

Although Ithe foregoing description is necessarily of a detailed character, in order to completely set for-th the invention, it is to be understood that the specific terminology is not intended to be Arestrictive or coniining and it is to be further understood that various rearrangements of parts and modifications of structural detail may be resorted to without departing from the scope or spirit `of vthe invention as herein claimed.

I claim:

1. Ina drilling apparatus, the combination with a supporting shell having a drill slidable thereon and a drill vsteel extending longitudinally from `the drill, of a drill steel Vcentralizar mounted on the forward end of the shell including an arm pivotally connected to said shell for rotation lengthwise of the shell, a pair of drill steel guiding fingers carried by said arm Vfor rotation therewith, an'd a pivotal connection'between said arm and each finger enabling independent rotation of said finger relative `to said arm toward or away from said drill steel within a plane passing through the longitudinal center axis: of said drill steel.

`2. In a drilling apparatus, .the combination with a supporting shell having a drill slidable thereon and a drill steel extending longitudinally from the drill, of a drill steel centralizer mounted on the forward end of the shell including an arm pivotally connected to said shell for longitudinal rotation relative thereto, a pair of parallel pivots in said arm one on each side of the drill steel, and a drill steel guiding finger on each pivot independently rotatable relative to said arm toward or away from said drill steel within a plane passing through the longitudinal center `axis of said drill steel.

3. In a drilling apparatus, the combination with a supporting shell having a drill sli'dable thereon and a drill steel extending longitudinal- Y ly from the drill, of a ldrill steel centralizer mounted on the forward end of the shell including a T-shaped arm carried by lthe shell, a pivotal connection between said shell and arm affording pivotal movement of the arm length- Wise of the shell, a pair of drill steel guide iingers carried b-y said arm, and a pivot in said arm for each finger enabling independent pivotal movement of said fingers toward or away from said drill steel within a plane passing through the longitudinal center axis thereof.

4. In a drilling apparatus, the combination with a supporting shell having a drill slidable thereon and a drill Vsteel extending longitudinally from the drill, of a drill steel centralizer mounted on the .end of the shell including an arm pivotally carried by the shell for swinging movement longitudinally of theshell, a pair of laterally spaced pivots journaled in said arm, and a drill steel guide linger carried by each pivot independently movable towa'rd or away from said drill steel within a plane passing through the longitudinal center axis thereof, said fingers extending at right angles from said pivots and ahead of the pivots relative to the direction of movement of said lingers away from said drill steel.

WILLIAM A. SMITH, Je. 

